• 제목/요약/키워드: Potent inhibitor

검색결과 683건 처리시간 0.034초

Diesel Exhaust Particles and Airway Inflammation: Effect of Nitric Oxide Synthase Inhibitors

  • Lim, Heung-Bin;Lee, Dong-Wook
    • Journal of Korean Society for Atmospheric Environment
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    • 제18권E2호
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    • pp.121-128
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    • 2002
  • This study was carried out to investigate if nitric oxide synthase (NOS) inhibitors modulate airway inflammation induced by diesel exhaust particles (DEP). N$\^$G/-nitro-L-arginine methyl ester (L-NAME), a potent constitutive NOS (cNOS) inhibitor, and aminoguanidine (AG), a selective inducible NOS (iNOS) inhibitor, were administered to mice in their drinking water for 7 weeks. Airway inflammation was elicited by the repeated intratracheal administration of DEP. The results showed that macrophages, inflammatory eosinophils and neutrophils in bronchoalveolar lavage (BAL) fluids by intratracheal DEP instillation were significantly suppressed in the mice treated with two NOS inhibitors toghther with DEP. The suppression of these cells was more effective in AG treated groups than in L -NAME treated groups. NOS inhibitor treatment also reduced interleukin -5 (IL-5 in the BAL fluids and lung homogenates. Additionally, it was found that eosinophil peroxidase (EPO) activity in the BAL fluids was also decreased by NOS inhibitor treatment. These results suggest that nitric oxide (NO) is produced in airway inflammation by repeated DEP instillation, and that iNOS inhibition as well as cNOS inhibition can play a modulating role in this airway inflammation by DEP.

Characterization of a New Antidementia $\beta$-Secretase Inhibitory Peptide from Rubus coreanus

  • Lee, Dae-Hyoung;Lee, Dae-Hyung;Lee, Jong-Soo
    • Food Science and Biotechnology
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    • 제17권3호
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    • pp.489-494
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    • 2008
  • In order to develop a potent antidementia $\beta$-secretase inhibitor from phytochemicals, $\beta$-secretase inhibitory activities of extracts from many medicinal plants and herbs were determined. Water extracts from Rubus coreanus showed the highest $\beta$-secretase inhibitory activity of 84.5%. After purification of the $\beta$-secretase inhibitor from R. coreanus using systematic solvent extraction, ultrafiltration, Sephadex G-10 column chromatography, and reverse-phase high performance liquid chromatography (HPLC), a purified $\beta$-secretase inhibitor with $IC_{50}$ inhibitory activity of $6.3{\times}10^3\;ng/mL$ ($1.56{\times}10^{-6}\;M)$ was obtained with a 0.08% solid yield. The molecular mass of the purified $\beta$-secretase inhibitor was estimated to be 576 Da by liquid chromatography-mass spectrometry (LC-MS) and $\beta$-secretase inhibitor also is a new tetrapeptide with the sequence Gly-Trp-Trp-Glu. The purified $\beta$-secretase inhibitory peptide inhibited $\beta$-secretase non-competitively and also show less inhibition on trypsin, however no inhibition on other proteases such as $\alpha$-secretase, chymotrypsin, and elastase.

Pharmacological properties of the reversible inhibitor of the gastric $H^+/K^+$ ATPase, AU-164

  • Kim, Hyo-Jung;Yum, Eul-Kgun;Choi, Jong-Kwon;Cheon, Hyae-Gyeong
    • Biomolecules & Therapeutics
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    • 제5권3호
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    • pp.228-232
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    • 1997
  • AU-164 was synthesized as a reversible gastric $H^+/K^+$ ATPase inhibitor, and its effects were tested in various systems. AU-164 inhibited rabbit gastric $H^+/K^+$ ATPase with an $IC_{50}$/ of 9 $\mu$M. On the other hand, AU-164 was a weak inhibitor for dog kidney $Na^+/K^+$ ATPasc, indicating the selectivity for gastric $H^+/K^+$ ATPase. The reversible property of the AU-164-induced inhibition of $H^+/K^+$ ATPase was confirmed by filtering the inhibition mixture through Sephadex G-25M column. In vivo basal acid secretion was also inhibited by AU-164 under the pylorus ligation of Sprague-Dawley rats. In addition, AU-164 protected dose dependently gastric lesion induced by ethanol in rats. The $ED_{50}$ value of 62 mg/kg p.o was estimated. These results suggest that AU-164 is a potent, selective and reversible gastric $H^+/K^+$ ATPase inhibitor, and that AU-164 has a potential use for the clinical therapeutics of peptic ulcer disease.

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Occurrence of OF494911 in the Fungal Mat formed by Surface Culture of Aspergillus niger F-580

  • Chun, Hyo-Kon;Chung, Myung-Chul;Ko, Hack-Ryong;Lee, Ho-Jae;Kho, Yung-Hee
    • Journal of Microbiology and Biotechnology
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    • 제5권5호
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    • pp.280-284
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    • 1995
  • Aspergi11us niger F-580, a potent producer of aminopeptidase M inhibitor, was isolated from the brown spots of plant leaves with a pathological trait. The inhibitory activity was found only in the fungal mat formed by surface culture of Aspergi11us niger F-580, but not in the culture supernatant or cell pellet. The inhibitor was purified from the hot water extract of this fungal mat by using chromatographies on Diaion HP-20, DEAE-cellulose, Sephadex G-l0 and YMC-ODS-AQ columns. The purified inhibitor was analyzed by UV, mass, and NMR spectroscopies, and identified as OF494911, which had been isolated as an aminopeptidase B inhibitor from Penicillium rugulosum OF4949

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각종 약용 식물로부터 피부노화 억제 관련 elastase 저해물질의 탐색 및 추출조건 (Screening and Extraction Condition of Anti-skin Aging Elastase Inhibitor from Medicinal Plants)

  • 곽윤진;이대형;김나미;이종수
    • 한국약용작물학회지
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    • 제13권6호
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    • pp.213-216
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    • 2005
  • 본 연구에서는 비교적 가격이 저렴하고 부작용이 없으면서 효능이 우수한 피부 노화 억제 제품을 개발하고자 먼저 다양한 종류의 약용식물을 대상으로 각종 유기용매 추출물을 제조한 후 이들의 elastase 저해 활성을 측정하여 우수 식물을 선발하고 이들로 부터 elastase 저해제 추출 최적조건을 검토하였다. 64종의 약용식물에 대한 다양한 추출물 가운데 복분자 메탄올 추출물의 elastase 저해 활성이 85%로 가장 높았고 이 저해물질은 메탄올로 $50^{\circ}C$에서 12시간 진탕 시켰을 때 가장 많이 추출 되었다.

Lipoxygenase Inhibitor from Defatted Nutmeg Seed

  • Kim, Hyo-Jin;Chung, Shin-Kyo;Park, Sang-Won
    • Preventive Nutrition and Food Science
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    • 제3권3호
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    • pp.216-220
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    • 1998
  • Lipoxygenase inhibitory acitivity of the methanolic extract of 60 different kinds of plant seeds was determined by a spectrophotometric method using a soybean lipoxigenase(SLO) and linolenic acid. Among the extracts examined, the methanolic extract of nutmeg(Myristical fragrans)seed showed the most potent SLO inhibitory activity. To isolate SLO inhibitor, hence, the defatted methanol extract was further partitioned with ether, ehtylacetate , and n-butanol , stepwise. The ether souble fraction was successively chromatographed on silica gel, Sephadex LH-20 and preparative TLC. Three phenolic compounds were isolated , and one of them showing a strong SLO inhibition activity was identified as a 2,6-dihydroxy-9-(3', 4', -dihydroxyphenyl)nonylphenone (IC50a=0.39$\mu\textrm{g}$/ml) by 1H-& 13C0NMR, IR, and MS spectroscopy.

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A New Potent Angiogenesis Inhibitor, FR-118487

  • Otsuka, Takanao;Ohkawa, Takehiko;Shibata, Toshihiro;Oku, Teruo;Okuhara, Masakuni;Terano, Hiroshi;Kohsaka, Masanobu;Imanaka, Hiroshi
    • Journal of Microbiology and Biotechnology
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    • 제1권3호
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    • pp.163-168
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    • 1991
  • A new angiogenesis inhibitor, FR-118487 was obtained by chemical modification of FR-111142 which was isolated from the fermentation products of Scolecobasidium arenarium F-2015. The antiangiogenic activity of FR-118487 was compared with that of the parent compound, FR-111142. In the endothelial cell proliferation test in vitro and the angiogenesis in the chick embryo chorioal-lantoic membrane assay, FR-118487 had about 5∼10 times stronger antiangiogenic activities than FR-111142. In addition, FR-118487 inhibited the angiogenesis in the rabbit corneal assay and suppressed the solid tumor growth in mice. These findings showed that FR-118487 would be a unique antiangiogenic agent with promising antitumor activity.

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석이에서 분리한 GE974의 ${\alpha}-Glucosidase$ 저해효과 (Inhibitory Effect of GE974 isolated from Gyrophora esculenta on ${\alpha}-Glucosidase$)

  • 최혁재;김동현;김남재
    • 생약학회지
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    • 제31권2호
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    • pp.196-202
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    • 2000
  • This study was conducted to search for the ${\alpha}-glucosidase$ inhibitor from the natural products. In the previous study, the water extract of Gyrophora esculenta exhibited a potent inhibitory effect on ${\alpha}-glucosidase$ activities. Then, by bioassay-guided fractionation followed by chromatographic separation of the water extract of Gyrophora esculenta, ${\alpha}-glucosidase$ inhibitor was isolated as GE974. GE974 showed significant inhibitory activities on some kinds of ${\alpha}-glucosidase$ in vitro. Its inhibitory mechanism seemed to be competitive for disaccharides. Also, it markedly inhibited ${\alpha}-glucosidases$ of intestine separated from both nondiabetics and diabetics.

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